s = input()
if int(s)>=30:
    print('Yes')
else:
    print('No') s = input() s input() input if int(s)>=30:
    print('Yes')
else:
    print('No') int(s)>=30 int(s) int s 30 print('Yes') print 'Yes' print('No') print 'No' s = input() input() s
s = input()
if int(s)>=30:
    print('Yes')
else:
    print('No')